Water service has returned to at least 10 homes in the Brushy Creek neighborhood of Williamson County after a 20-foot sinkhole opened up Thursday morning and revealed a cave.

According to a press release from the Williamson County Public Information Office, county officials and environmental consultants found the cave in Cambria Drive starts approximately in the middle of the roadway 20 feet west of the curb, and heads east by approximately 170 feet.

The height of the cave was found to have varying heights of approximately 22 feet near the entrance with an average of 10 to 15 feet throughout.

According to a tweet from the sheriff's office, the sinkhole is located in the 8400 block of Cambria Drive, just north of Highway 45 and two miles south of Brushy Creek. The block was closed and officials said it will remain so for several weeks during the remediation effort.

A 20ft deep sinkhole has opened up in the 8400 Blk of Cambria Dr. due to water leak in the Woods of Brushy creek subdivision. Traffic is being diverted around the scene and residents in the area have been notified. pic.twitter.com/NJ87U6Drhp

— WilCo Sheriff's PIO (@WilCoSheriffPIO) February 8, 2018

Traffic was diverted around the area while crews investigated.

Municipal Utility District officials said the hole was caused by the roof of a cave that collapsed on top of a water line.

Michelle Mitchell lives in one of the three homes above the cave.

"It's not how you expect to start your day literally with, 'Hey, a cave opened up,'" she said.

At 3 a.m., some homeowners called the Municipal Utility District to complain about low water pressure, while others said they had no water at all, which was what prompted the discovery of the cave. By 2:50 p.m. Thursday, the Brushy Creek MUD reported that all 10 homes remained without water but, the service was restored at around 4 p.m.

Officials said the sinkhole is one of the biggest they've ever seen.

"Usually, they're fairly narrow," said General Manager for Brushy Creek MUD Mike Petter. "You almost have to crawl on your belly to get through them. But this one's large. It looks like you could have walked around in it before it collapsed."

An environmentalist was also at the scene to assess the damage. Williamson County is working with the Texas Commission on Environmental Quality to determine the best solution to repair the neighborhood where the cave was revealed.

County officials said hydrogeologists were on site Thursday to map the cave.

It is still unknown exactly what caused the opening, however, officials said the initial examination shows that the limestone bed that forms the cave's ceiling is scored and thinner where the utility lines were installed, and the cave ceiling seems to be more stable outside of that area.

On Monday, structural engineers will evaluate the cave to determine the stability of the cave as well as options for repairs. Officials are encouraging the public to stay safe by staying behind the safety fencing.